U.S. patent number 4,518,325 [Application Number 06/512,863] was granted by the patent office on 1985-05-21 for aerifying device for whirlpool bath or tub.
Invention is credited to James E. Kingston.
United States Patent |
4,518,325 |
Kingston |
May 21, 1985 |
Aerifying device for whirlpool bath or tub
Abstract
An electric motor has an upright axial drive shaft carrying a
blower at the bottom and a separate fan at the top. The blower
supplies a strong flow of air for aerifying water contained in a
whirlpool bath or tub and the fan supplies a secondary flow of air
for cooling the motor. A housing mounting the motor has a bottom
bowl section forming a first plenum for air blown by the blower and
a top dome section forming a second plenum for air blown by the
fan. The two plenums are substantially sealed from each other so
that the fan continues to supply air to cool the motor and maintain
it at its designed operating temperature regardless of whether or
not the primary air flow is prevented or reduced, such as by an
obstruction.
Inventors: |
Kingston; James E. (Arlington,
WA) |
Family
ID: |
24040918 |
Appl.
No.: |
06/512,863 |
Filed: |
July 11, 1983 |
Current U.S.
Class: |
417/368;
417/423.14 |
Current CPC
Class: |
A61H
33/028 (20130101); F04D 29/582 (20130101); A61H
2201/1207 (20130101) |
Current International
Class: |
A61H
33/02 (20060101); F04D 29/58 (20060101); F04B
017/00 () |
Field of
Search: |
;417/368,366,423A,423R,369,372,373,360,410,424 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Callaghan; Thomas F.
Assistant Examiner: Cuomo; Peter M.
Attorney, Agent or Firm: Brown; Ward Beach; Robert W.
Claims
I claim:
1. For use with a by-pass vacuum motor having:
an axial drive shaft;
electrically-powered workings for rotating the drive shaft;
blower means driven by rotation of the drive shaft and carried at
one end portion thereof for supplying a primary flow of air;
a blower casing separating the electrically-powered workings from
the blower means, enclosing the blower means and having an air
inlet for intake of air into such casing generally axially of the
drive shaft at the blower means end of the drive shaft and air
outlet means for discharging air from such casing generally
radially of the drive shaft; and
fan means mounted outside the blower casing and driven by rotation
of the drive shaft for supplying a secondary flow of air to cool
the electrically-powered workings;
the improvement comprising a housing for mounting the by-pass
vacuum motor with its axial drive shaft upright and its blower
means at the bottom and adapting the by-pass vacuum motor for use
as an aerifying device for baths or tubs, said housing
comprising:
a bowl portion having an upright peripheral wall encircling the
blower casing and extending downward a substantial distance below
the blower casing, said bowl portion having an air inlet and an air
outlet and forming a first plenum for air discharged from the
blower casing; and
an air inlet conduit having one end portion sealed around the air
inlet of the blower casing and the other end portion sealed around
the air inlet of said housing bowl portion, said air inlet conduit
extending through the first plenum formed by said bowl portion for
conveying air from outside said bowl portion to the blower casing
air inlet.
2. The housing defined in claim 1, in which the bowl portion has a
horizontal bottom extending inward from the bottom portion of the
upright peripheral wall and spaced below the blower casing, the
bowl portion air inlet extending through said bowl portion bottom
and being registered axially of the drive shaft with the air inlet
of the blower casing, and the air inlet conduit extending
vertically upward through the housing bowl portion from its bottom
air inlet to the air inlet of the blower casing.
3. The housing defined in claim 2, including base means beneath the
housing bowl portion, mounting the housing bowl portion
freestanding and spaced above the ground and having air inlet means
for intake of air into said base means for entry into the air inlet
conduit.
4. The housing defined in claim 1, including a dome portion
extending upward from the bowl portion, encircling the fan means
and the electrically-powered workings of the motor and forming a
second plenum for air blown by the fan means, said second plenum
and the first plenum formed by the bowl portion being substantially
sealed from each other.
5. The housing defined in claim 4, in which the housing bowl
portion upright peripheral wall is spaced outward from the blower
casing, the dome portion including an annular flange extending
inward from the top of such upright peripheral wall and having an
inner edge portion sealed to the blower casing to seal the first
and second plenums from each other.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device for supplying a strong
flow of air for aerifying water contained in a whirlpool bath or
tub.
2. Prior Art
Some known whirlpool baths and tubs have circumferentially spaced
air inlet holes positioned below the water level and communicating
with a circumferentially extending plenum chamber. An air
compressor or blower supplies a strong flow of air to the plenum
chamber through appropriate conduits to aerify the water contained
in the bath or tub.
One known air compressor or blower marketed for this use has an
electric motor mounted upright in a housing. A single blower or fan
carried above and driven by the motor draws air through an inlet in
the top of the housing. Such air is blown down along the electrical
works of the motor to cool it and is discharged from the housing
through a horizontally extending outlet tube into the conduit
connected to the bath or tub plenum.
If the conduit or the air holes of the bath or tub are obstructed
or clogged, the electric motor continues to operate but the flow of
air through it is prevented. Consequently, the motor can burn out
or at least overheat so as to shorten its life. Similarly, at
start-up the aerifying airflow must overcome the substantial back
pressure caused by the water in the spa or tub, and during this
period the air flow through the motor may be insufficient to keep
the motor at its designed operating temperature.
In addition, the water in the bath or tub usually is heated and,
when the electric motor is not operating, water vapor can be
conveyed through the conduit into the motor. Condensation can occur
inside the motor, or at least the motor is subjected to a humid
environment that can cause corrosion and shorten the life of the
motor.
SUMMARY OF THE INVENTION
The principal object of the present invention is to provide a novel
device for supplying a strong flow of air for aerifying water
contained in a conventional whirlpool bath or tub, utilizing an
electric motor driving a fan or blower but in a form assuring a
flow of air through the electrical works of the motor sufficient to
maintain it at its designed operating temperature regardless of
whether or not the aerifying air outlet is obstructed.
An additional object is to provide such a device in a form assuring
that the electrical works of the motor are not subjected to a
potentially corrosive humid environment.
A further object is to provide such a device in a compact, simple
form easy and inexpensive to manufacture.
These and other objects are accomplished by the aerifying device of
the present invention described in detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded top perspective of an aerifying device for
whirlpool baths or tubs in accordance with the present invention;
and FIG. 2 is a corresponding top perspective of such device with
its parts assembled.
FIG. 3 is a side elevation of such device; and FIG. 4 is a somewhat
diagrammatic axial section taken along line 4--4 of FIG. 3.
DETAILED DESCRIPTION
The aerifying device of the present invention is intended to be
used to supply a strong flow of air for aerifying the water in a
conventional whirlpool bath or tub. The component parts of such
device are best seen in FIG. 1. In general, such device includes an
electric motor 10 mounted in a housing having a base 20, a bottom
section or bowl 30 and a top section or dome 40. The top of the
housing is covered by an upper shroud 50.
It is important for the purposes of the present invention that the
electric motor 10 be of a type having separate fans or blowers for
supplying, respectively, a primary airflow used to aerify the water
in the bath or tub and a secondary airflow for cooling the
electrical works of the motor. An example of such a motor is the
"Lamb By-Pass Vacuum Motor" sold by Amatek Inc. through its Lamb
Electric Division of Kent, Ohio.
With reference to FIG. 3 which shows such a motor somewhat
diagrammatically and partially in section, the electrical works of
the motor 10 are enclosed by a cylindrical motor casing 11 and
drive an axial shaft 12 carrying a centrifugal blower 13 at one end
and propeller-type fan 14 at the other end. The blower 13 is
enclosed in a close-fitting blower casing 15 having a central inlet
aperture 16 through which air is drawn generally axially into such
casing and a row of circumferentially spaced outlet apertures 17
through which such air is blown out of the casing.
The fan 14 is enclosed in a fan casing 18 having air inlet
apertures 19 through which air is drawn generally axially inward.
Such air is forced through the motor casing 11 along the electrical
works of the motor to cool it and then is discharged from the end
of the motor casing remote from the fan.
In accordance with the present invention, the motor 10 is mounted
with its shaft 12 upright and its main blower 13 at the bottom. A
generally frustoconical base 20 has a circumferential horizontal
support flange 21 bent outward from the bottom of the generally
upright wall 22 which has circumferentially spaced air inlet holes
23. The dished top 24 of the base is bent inward from the top of
such upright wall and has a central aperture in which the bottom
end portion of an upright air inlet tube 25 is mounted. The bottom
end of the air inlet tube is spaced above the bottom of the base 20
to allow a free flow of air into such tube; and the top end of the
air inlet tube is sealed to the bottom of the blower casing 15 by a
resilient, circular gasket 26 encircling the bottom air inlet
aperture 16 of the blower casing.
The dished top 24 of the base supports the generally cylindrical
bottom housing section or bowl 30. The bottom 31 of such bowl has a
central aperture registered with the aperture of the base 20 and
encircling the bottom end portion of the inlet tube 25. The upright
peripheral wall 33 of the bowl extends upward to about the top of
the blower casing 15 and is spaced outward from the casing outlet
apertures 17. The inner end portion of a horizontal, generally
radially extending outlet tube 34 is fitted in an aperture in the
wall 33 of the bowl 30.
In combination with the blower casing 15, the top of the bowl 30 is
closed by the top housing section or dome 40. Such dome has a
bottom upright circumferential lip 41 fitted over the upper end
portion of the wall 33 of the bowl 30. An annular planar web 42 is
bent horizontally inward from such lip 41 and has its inner end
portion closely adjacent and sealed to the top of the blower
housing 15. The peripheral wall 43 of the dome 40 extends upward
from the web 42, is spaced outward from the central portion of the
motor 10 and has an air outlet hole 44. The top 45 of the dome is
curved inward from the wall 43 and has a central aperture closely
encircling and sealed to the fan casing 18.
As best seen in FIG. 1, the top shroud 50 is mounted over the upper
housing section or dome 40 by a bracket 51. FIG. 4 shows the
horizontal top 52 of such shroud spaced above the apertured top of
the fan housing 18 of the electric motor. The upright peripheral
shroud wall 53 extends downward from such top 52 to about the lip
41 of the top housing section 40. The wall 53 is spaced outward
from the lip 41 to form an annular air inlet passage.
FIG. 4 also illustrates the separate airflows created by the
aerifying device of the present invention. The centrifugal blower
13 of the electric motor draws air inward through the holes 23 in
the base 10 and upward through the inlet tube 25 and the aperture
16 in the bottom of the blower casing 15. Such air is blown out of
such casing 15 through its circumferentially spaced apertures 17
into the chamber or plenum formed by the bottom housing section 30,
and out through the horizontal outlet tube 34 which can be
connected to a conduit for supplying the air to a bath or tub.
The fan 14 of the motor draws a separate flow of air upward through
the space between the shroud 50 and the top housing section 40.
Generally upright gaskets 46, shown in FIG. 1, engaged between the
wall 43 of the top housing section 40 and the wall 53 of the shroud
50 guide the incoming flow of air to the inlet apertures 19 in the
top of the fan casing 18. Such air is blown down through the motor
casing 11 to cool the electrical workings of the motor and is
discharged into the upper plenum formed by the top housing section
40, then out through the outlet hole 44 in such upper housing
portion. A generally U-shaped gasket 47 guides the outflowing air
downward to the space between the upper shroud 50 and the bottom
end portion of the top housing section 40 to prevent such air from
immediately recirculating back through the motor.
Regardless of whether or not an obstruction occurs which prevents a
full flow of air through the bottom housing section 20, cooling air
continues to be supplied to the motor by the fan 14 so that it will
not burn out or overheat. In addition, the bottom plenum formed by
such bottom housing section is substantially sealed from the upper
plenum formed by the top housing section which contains the
electrical works of the motor, so that even when the motor is not
operating such electrical works are not subjected to a potentially
corrosive humid environment. For example, condensation may occur in
the bottom housing section 30 from warm water vapor conveyed into
it through the outlet tube 34 connected to the bath or tub, but
condensation will not occur in the top housing section because it
is sealed from the bottom housing section. Also, by positioning the
main blower 13 at the bottom, water will not collect on the blower
or in the area of the seal around the motor shaft 12, but rather
will drip or run down out through the inlet aperture 16 of the
blower casing 15.
* * * * *